Skull Crushers question (yes, again), with a video this time

[IronFist]

Would you say this (http://www.exrx.net/WeightExercises/Triceps/BBLyingTriExt.html) guy has too much extraneous upper arm movement?

He's definately NOT "crushing the skull," since he brings it so far back.

The way in the video is actually the way I was taught to do it, but it seems much easier to do it that way than if you leave your upper arms perfectly vertical the whole time and bring it down over your skull.

So I'm wondering if tougher (vertical upper arms) = more effective? It's obviously just an issue of leverage, so is worse leverage with less weight equivalent to better leverage with more weight?

[Ford Prefect]

With different angles, different muscles are involved. The reason why power guys like skull crushers so much is that they work the elbow extensors (triceps & aconeus) which is what is used in benching rather than a straight up tricep isolation exercise. Your arm position is also in relatively the same position as when you bench.

[IronFist]

Hmm. So which way are you saying is better for power lifting?

[Ford Prefect]

Skull crushers, elbows out extensions, jm press, etc. You'll notice that they all recruit the aconeus to a greater degree than regular tricep extenions, push-downs, etc.

[IronFist]

I mean which method of doing skull crushers is better: with the upper arms vertical the whole time and the bar coming down over the skull, or the way the guy does it in the video I linked to?

[Ford Prefect]

That guy isn't doing skull crushers. He's doing laying tricep extensions. It even says that on the page. A skull crusher is called a "skull crusher" for the exact reason that you bring it down right over your head. If you drop it, you will crush your skull... From that angle, you are in the same arm position as if you were benching, the aconeus is activated to a greater degree, and the nature of the exercise mimicks a recovery after letting your bench get out of the groove, which helps powerlifters as well. (that's one of the benefits to the good morning as well)

Not only that but you can use greater poundages and since tricep heads are only recruited as tension builds, theoretically you can develop the triceps to a greater degree. This is why static bench holds and 2" presses nail the triceps the way they do.

[IronFist]

Heh, I suck. I thought skull crushers were just a slang name people gave lying triceps extensions. Oops.

[Ford Prefect]

*******.